European Journal of Radiology

Editorial Board

2010-02-01

The value of brain CT findings in acute methanol toxicity

2010-02-01

Abstract: Objective: Due to depressant effects of methanol on the central nervous system, brain computed tomography (CT) scan has been introduced as a diagnostic device in methanol intoxication. The authors aimed to present brain CT findings in patients with acute methanol intoxication and to determine signs associated with death.Materials and methods: This cohort study involved 42 consecutive patients with acute methanol intoxication. Inclusion criteria were consisted of characteristic clinical presentation of methanol poisoning, and metabolic acidosis with increased anion and osmolar gaps. Brain CT scans without contrast medium were obtained. To determine the association between the CT findings and death, the chi-square test or the Fisher's exact test, odds ratio (OR) and its 95% confidence interval (95% CI) were calculated.Results: Twenty-eight patients (66.6%) had a total of 55 abnormal findings on brain CT, in which bilateral putaminal hypodense lesions was the most common manifestation (27 cases, 96.4%). Putaminal hemorrhage with varying degrees was observed in 7 patients (25%). Six patients (21.4%) had low attenuation lesions in the subcortical white matter of the insula. A significant association was observed between putaminal hemorrhage (OR=8, 95% CI=1.187–53.93, P=0.018) and subcortical necrosis of the insula (OR=11, 95% CI=1.504–80.426, P=0.007) with death.Conclusion: In addition to clinical and laboratory findings, presence of putaminal hemorrhage and insular subcortex white matter necrosis are associated with a poor clinical outcome in patients with methanol poisoning.

Relative cerebral blood volume measurements of low-grade gliomas predict patient outcome in a multi-institution setting

2010-02-01

Abstract: Background/purpose: The prognostic value of defining subcategories of gliomas is still controversial. This study aims to determine the utility of relative cerebral blood volume (rCBV) in predicting clinical response in patients with low-grade glioma at multiple institutions.Materials and methods: Sixty-nine patients were studied with dynamic susceptibility contrast-enhanced perfusion MRI at two institutions. The pathologic diagnoses of the low-grade gliomas were 34 astrocytomas, 20 oligodendroglioma, 9 oligoastrocytomas, 1 ganglioglioma and 5 with indeterminate histology.Wilcoxon tests were used to compare patients in different response categories with respect to baseline rCBV. Kaplan–Meier curve and log-rank tests were used to predict the association of rCBV with time to progression.Results: At both institutions, patients with an adverse event (progressive disease or death) had a significantly higher baseline rCBV than those without (complete response or stable disease) (p value=0.0138).The odds ratio for detecting an adverse event when using rCBV was 1.87 (95% confidence interval: 1.14–3.08). rCBV was significantly negatively associated with time to progression (p=0.005). The median time to progression among subjects with rCBV>1.75 was 365 days, while there was 95% confidence that the median time to progression was at least 889 days among subjects with rCBV<1.75.Conclusion: Our study suggests not only that rCBV measurements correlate well with time to progression or death, but also that the findings can be replicated across institutions, which supports the application of rCBV as an adjunct to pathology in predicting glioma biology.

Oculomotor paralysis: 3D-CISS MR imaging with MPR in the evaluation of neuralgic manifestation and the adjacent structures

Xiaoli Sun, Changhu Liang, Cheng Liu, Shuwei Liu, Kai Deng, Jingzhen He — 2010-02-01

Abstract: Purpose: To evaluate the value of three-dimensional (3D) constructive interference in steady-state (CISS) magnetic resonance (MR) imaging with multi-planar reconstruction (MPR) in displaying the relationship between the oculomotor nerve and its adjacent structures for patients with oculomotor paralysis.Materials and methods: 17 consecutive patients with oculomotor paralysis were examined with 3D-CISS and conventional spin-echo (SE) sequences on a 1.5-Tesla MR system. Original transverse and MPR images were used for image interpretation. The features of the oculomotor nerve and its adjacent structures were identified. The diagnosis was surgically confirmed in all patients.Results: Through 3D-CISS with MPR images, obvious relationship of the oculomotor nerve and its adjacent structures was demonstrated on 17 patients. Of those oculomotor nerves, 15 were compressed by the arteries (n=15), one by the craniopharyngioma (n=1), and another one by the neurofibroma (n=1).Conclusion: 3D-CISS MR imaging with MPR provides an excellent way to characterize the relationship between the nerve and its adjacent structures in the cisternal segment of the oculomotor nerve in the patients with oculomotor paralysis. Moreover, this method shows anatomical details for imaging diagnosis and surgical procedure.

CT–MR image data fusion for computer-assisted navigated surgery of orbital tumors

2010-02-01

Abstract: Purpose: To demonstrate the value of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the preoperative assessment of orbital tumors, and to present, particularly, CT and MR image data fusion for surgical planning and performance in computer-assisted navigated surgery of orbital tumors.Materials and methods: In this retrospective case series, 10 patients with orbital tumors and associated complaints underwent MDCT and MRI of the orbit. MDCT was performed at high resolution, with a bone window level setting in the axial plane. MRI was performed with an axial 3D T1-weighted (w) gradient-echo (GE) contrast-enhanced sequence, in addition to a standard MRI protocol. First, MDCT and MR images were used to diagnose tumorous lesions compared to histology as a standard of reference. Then, the image data sets from CT and 3D T1-w GE sequences were merged on a workstation to create CT–MR fusion images that were used for interventional planning and intraoperative image guidance. The intraoperative accuracy of the navigation unit was measured, defined as the deviation between the same landmark in the navigation image and the patient. Furthermore, the clinical preoperative status was compared to the patients’ postoperative outcome.Results: Radiological and histological diagnosis, which revealed 7 benign and 3 malignant tumors, were concordant in 7 of 10 cases (70%). The CT–MR fusion images supported the surgeon in the preoperative planning and improved the surgical performance. The mean intraoperative accuracy of the navigation unit was 1.35mm. Postoperatively, orbital complaints showed complete regression in 6 cases, were ameliorated notably in 3 cases, and remained unchanged in 1 case.Conclusion: CT and MRI are essential for the preoperative assessment of orbital tumors. CT–MR image data fusion is an accurate tool for planning the correct surgical procedure, and can improve surgical results in computer-assisted navigated surgery of orbital tumors.

Dynamic MR dacryocystography in patients with epiphora

R. Cubuk, N. Tasali, S. Aydin, B. Saydam, T. Sengor — 2010-02-01

Abstract: Objective: The purpose of this study was to investigate the diagnostic value of dynamic MRI dacryocystography (dMR-DCG) for the assessment of nasolacrimal drainage system (NLDS).Methods: The study population consisted of 35 patients with a history of epiphora. Each patient underwent bilateral dMR-DCG and conventional dacryocystography (DCG) to assess the NLDS. Two radiologists, who were unaware of the clinical data, evaluated the images separately for the level of obstruction at the nasolacrimal passage and the presence or absence of lacrimal sac dilatation. The findings from the dMRI-DCG and DCG images were compared. DCG was considered to be the gold standard imaging technique.Results: dMRI-DCG had a sensitivity of 90.5% and a specificity of 89.3% to detect nasolacrimal passage. In 24 out of 70 NLDS that were assessed, there was 100% agreement between the dMRI-DCG and DCG images in the detection of the obstructed level in the nasolacrimal pathway. The lacrimal sac dilatation finding detected by DCG was not observed by dMRI-DCG in only two patients, in whom there was a prior history of dacryocystorhinostomy (DCR) operation. These findings suggest that dMRI-DCG has 94.3% sensitivity and 100% specificity for the diagnosis of lacrimal sac dilatation.Conclusion: dMRI-DCG is an easily performed, minimally invasive imaging technique to identify the presence or absence of obstruction and its level, and lacrimal sac dilatation in the evaluation of NLDS. dMRI-DCG does not require the use of contrast material and ionizing radiation and provides functional information by depicting dynamic behaviour. Thus, dMRI-DCG could be useful as a reliable diagnostic imaging technique in many patients prior to surgery.

Ultrasonographic evaluation of the iatrogenic peripheral nerve injuries in upper extremity

Nuri Karabay, Tulgar Toros, Yalçın Ademoğlu, Sait Ada — 2010-02-01

Abstract: The aim of our study is to assess the efficiency of the ultrasonography (US) in the diagnosis of peripheral nerve injury. This study includes nine patients (six radial, one median and two posterior interosseous (PIO) nerves) with peripheral nerve injury diagnosed by clinical and electrophysiological methods in the last 3 years. Preoperatively, an ultrasonographic examination was performed and correlated with physical exam and surgical findings. Five patients, who were diagnosed as peripheral nerve transection by US, underwent surgery. The ultrasonographic findings were concordant with the intraoperative findings. Axonal swelling alone was found in the remaining three patients, who were treated conservatively because of preserved nerve continuity without display of nerve compression. In one patient, we were unable to visualize the nerve due to obesity and soft tissue edema. High-resolution US provide morphological information about the exact location, intensity and extent of the nerve injuries, facilitating the preoperative diagnosis. Thus, US may be a useful method for planning optimal treatment strategy in especially iatrogenic nerve injuries.

18F-FDG-PET/CT of orofacial tumors, a value of whole-body imaging approach

2010-02-01

Abstract: Aim: Staging of head and neck tumors is one of the most difficult tasks in imaging techniques, due to the very complicated head and neck anatomy and serious problems with the differentiation of reactive enlarged lymph nodes and lymph nodes involved with metastases. The aim of the study was to evaluate the validity of the whole-body approach in the assessment of head and neck malignancies using 18F-FDG-PET/CT.Materials and methods: The analysis of a group of 1750 consecutive whole-body procedures in all indications of 18F-FDG-PET/CT was made according to: the presence of orofacial tumors; their histology; findings concerning the spread outside head and neck region; and findings concerning the primary staging or restaging. The examinations of head and neck tumors were performed after intravenous application of the 18F-FDG and its accumulation for one hour. Drinking and speaking is restricted during this accumulation to prevent artificial muscle 18F-FDG uptake and to minimize false positive findings. In our hospital, high resolution PET is followed by the sub-millimeter isotropic acquisition of CT data after intravenous application of an iodinated contrast material. The acquisitions of head and neck region and trunk are performed separately to obtain optimal resolution in both regions.Results: 105 examinations of the orofacial tumors were performed on 87 patients in a group of 1750 consecutive PET/CT examinations. The ratio between primary staging and restaging was 3:7. The most frequent indications were carcinomas of the tongue (19 examinations) and carcinomas of the salivary glands (19 examinations). The metastatic spread of the tumor outside the region of the head and neck was noted in 12 cases.Conclusion: Our findings of distant metastases confirmed the importance of the use of whole-body PET/CT in this indication.

Demonstration of pulmonary perfusion heterogeneity induced by gravity and lung inflation using arterial spin labeling

Li Fan, Shi-yuan Liu, Xiang-sheng Xiao, Fei Sun — 2010-02-01

Abstract: Objective: To evaluate the effect of gravity and lung inflation on pulmonary perfusion heterogeneity in human lung using an arterial spin labeling (ASL) sequence called flow sensitive alternating inversion recovery (FAIR).Materials and methods: Magnetic resonance imaging of lung perfusion using arterial spin labeling sequence was performed in supine position in ten healthy volunteers on a 1.5T whole body scanner (GE Healthcare). Five coronal slices at an interval of 3cm from dorsal to ventral (labeled as P3, P6, P9, P12, P15, sequently) were obtained when the volunteers performed breath holding on end expiration and the relative pulmonary blood flow (rPBF) was measured. Then, another coronal perfusion-weighted image of P3 slice was obtained on end inspiration. Tagging efficiency of pulmonary parenchyma with IR (ΔSI), rPBF and area of the P3 slice were analyzed.Results: (1) Along the direction of gravity, a gradient was visually perceived as a vertical increase in rPBF. There were significant statistic differences in rPBF between any two coronal planes except that between P12 and P15. In supine position, regression coefficients of right and left lung were −4.98 and −5.16, respectively. This means that rPBF decreased 4.98 (right) and 5.16 (left) for each centimeter above the dorsal. No statistical difference was seen between ROIs placed along iso-gravitational plane. (2) For a same slice, there were significant statistic differences in ΔSI, rPBF and area at different respiratory phases (P<0.05). Greater ΔSI and more perfusion were observed on end expiration than on end inspiration. The area was larger on end inspiration than on end expiration.Conclusion: Both gravity and respiratory phase are important determinants of pulmonary perfusion heterogeneity. FAIR is sensitive to demonstrate gravity- and respiratory phase-dependent differences in lung perfusion. Positioning the patient so that the area of interest is down-gravity and asking patient to hold breath on end expiration may help in detection of perfusion defects.

31P magnetic resonance spectroscopy to measure in vivo cardiac energetics in normal myocardium and hypertrophic cardiomyopathy: Experiences at 3T

2010-02-01

Abstract: Background: 31P magnetic resonance spectroscopy (MRS) allows measurement of in vivo high-energy phosphate kinetics in the myocardium. While traditionally 31P cardiac spectroscopy is performed at 1.5T, cardiac MRS at higher field strength can theoretically increase signal to noise ratio (SNR) and spectral resolution therefore improving sensitivity and specificity of the cardiac spectra. The reproducibility and feasibility of performing cardiac spectroscopy at 3T is presented here in this study in healthy volunteers and patients with hypertrophic cardiomyopathy.Methods: Cardiac spectroscopy was performed using a Phillips 3T Achieva scanner in 37 healthy volunteers and 26 patients with hypertrophic cardiomyopathy (HCM) to test the feasibility of the protocol. To test the reproducibility a single volunteer was scanned eight times on separate occasions. A single voxel 31P MRS was performed using Image Selected In vivo Spectroscopy (ISIS) volume localization.Results: The mean phosphocreatine/adenosine triphosphate (PCr/ATP) ratio of the eight measurements performed on one individual was 2.11±0.25. Bland Altman plots showed a variance of 12% in the measurement of PCr/ATP ratios. The PCr/ATP ratio was significantly reduced in HCM patients compared to controls, 1.42±0.51 and 2.11±0.57, respectively, P<0.0001. (All results are expressed as mean±standard deviation).Conclusions: Here we demonstrate that cardiac 31P MRS at 3T is a reliable method of measuring in vivo high-energy phosphate kinetics in the myocardium for clinical studies and diagnostics. Based on our data an impairment of cardiac energetic state in patients with hypertrophic cardiomyopathy is indisputable.

MR image analysis: Longitudinal cardiac motion influences left ventricular measurements

2010-02-01

Abstract: Background: Software for the analysis of left ventricular (LV) volumes and mass using border detection in short-axis images only, is hampered by through-plane cardiac motion. Therefore we aimed to evaluate software that involves longitudinal cardiac motion.Methods: Twenty-three consecutive patients underwent 1.5-Tesla cine magnetic resonance (MR) imaging of the entire heart in the long-axis and short-axis orientation with breath-hold steady-state free precession imaging. Offline analysis was performed using software that uses short-axis images (Medis MASS) and software that includes two-chamber and four-chamber images to involve longitudinal LV expansion and shortening (CAAS-MRV). Intraobserver and interobserver reproducibility was assessed by using Bland–Altman analysis.Results: Compared with MASS software, CAAS-MRV resulted in significantly smaller end-diastolic (156±48ml versus 167±52ml, p=0.001) and end-systolic LV volumes (79±48ml versus 94±52ml, p<0.001). In addition, CAAS-MRV resulted in higher LV ejection fraction (52±14% versus 46±13%, p<0.001) and calculated LV mass (154±52g versus 142±52g, p=0.004). Intraobserver and interobserver limits of agreement were similar for both methods.Conclusion: MR analysis of LV volumes and mass involving long-axis LV motion is a highly reproducible method, resulting in smaller LV volumes, higher ejection fraction and calculated LV mass.

Diagnostic accuracy of 64 multislice CT angiography in the assessment of coronary in-stent restenosis: A meta-analysis

Zhonghua Sun, Abdulrahman Marzouq D. Almutairi — 2010-02-01

Abstract: Purpose: The aim of this study was to perform a meta-analysis of the diagnostic accuracy of 64-slice CT angiography for the detection of coronary in-stent restenosis in patients treated with coronary stents when compared to conventional coronary angiography.Materials and methods: A search of PUBMED/MEDLINE, ProQuest and Cochrane library databases for English literature was performed. Only studies comparing 64-slice CT angiography with conventional coronary angiography for the detection of coronary in-stent restenosis (more than 50% stenosis) were included for analysis. Sensitivity and specificity estimates pooled across studies were tested using a fixed effects model.Results: Fourteen studies met selection criteria for inclusion in the analysis. The mean value of assessable stents was 89%. Prevalence of in-stent restenosis following coronary stenting was 20% among these studies. Pooled estimates of the sensitivity and specificity of overall 64-slice CT angiography for the detection of coronary in-stent restenosis was 90% (95% CI: 86%, 94%) and 91% (95% CI: 90%, 93%), respectively, based on the evaluation of assessable stents. Diagnostic value of 64-slice CT angiography was found to decrease significantly when the analysis was performed with inclusion of nonassessable segments in five studies, with pooled sensitivity and specificity being 79% (95% CI: 68%, 88%) and 81% (95% CI: 77%, 84%). Stent diameter is the main factor affecting the diagnostic value of 64-slice CT angiography.Conclusion: Our results showed that 64-slice CT angiography has high diagnostic value (both sensitivity and specificity) for detection of coronary in-stent restenosis based on assessable segments when compared to conventional coronary angiography.

Dual-source computed tomography: Estimation of radiation exposure of ECG-gated and ECG-triggered coronary angiography

2010-02-01

Abstract: Purpose: The aim of the study was to estimate radiation exposure of coronary calcium scoring and angiography using ECG-gated and ECG-triggered dual-source computed tomography.Materials and methods: An Alderson Rando phantom equipped with thermoluminescent dosimeters was used for all dose measurements. Effective dose was calculated according to ICRP 103. Radiation exposure was performed on a dual-source computed tomography (DSCT) scanner with standard protocols for calcium scoring (DSCT-Ca) and coronary angiography (DSCTA) at different heart rates (40–100 beats/min). Furthermore, a scanning protocol with ECG-triggering as well as a standard chest CT scan were evaluated.Results: Depending on gender, heart rate and ECG-pulsing, the effective dose of a complete cardiac DSCT (DSCT-Ca and DSCTA) scan varies from 10.2 to 32.6mSv. The effective radiation dose increased significantly with lower heart rates (p<0.035). ECG-pulsing reduced the radiation exposure significantly in DSCTA (p<0.001). Due to breast tissue in the primary scan range, females’ doses showed an increase up to 69.9% compared to males in scan protocols without ECG-pulsing. Prospective ECG-triggered DSCTA resulted in estimated effective doses from 2.8mSv (males) to 4.1mSv (females).Conclusion: The ECG-pulsing technique has proven its effectiveness to reduce effective dose in coronary CT angiography and is recommended for all patients with regular heart rates. The patient's heart rate influences the radiation exposure with a significant decrease at higher heart rates. Due to its lower dose, ECG-triggered DSCTA should be implemented for special indications, i.e. for diagnosis of pathologies of the aortic root and the ascending aorta.

Imaging anti-angiogenic treatment response with DCE-VCT, DCE-MRI and DWI in an animal model of breast cancer bone metastasis

2010-02-01

Abstract: As current classification systems for the assessment of treatment response in bone metastasis do not meet the needs of oncologists, new imaging biomarkers are desirable. Therefore, the diagnostic impact of dynamic contrast enhanced (DCE)-volumetric computed tomography (VCT) (descriptive analysis), DCE-MRI (two-compartment model) and diffusion weighted imaging (DWI) for monitoring anti-angiogenic therapy effects of the VEGF antibody bevacizumab in breast cancer bone metastases in rats was studied. Nude rats (n=8 animals treated with bevacizumab and n=9 untreated control rats) with site-specific osteolytic bone metastasis of the hind leg were imaged with a 1.5T clinical MRI-scanner in an animal coil as well as in a volumetric CT-scanner at days 30, 40, 50 and 60 after inoculation of MDA-MB-231 human breast cancer cells. From these data, osteolytic lesion size (OLS), peak enhancement (PE), area under the curve (AUC), amplitude (A), exchange rate constant (kep) and apparent diffusion coefficient (ADC) were determined in bone metastases. Prior to changes in OLS (p≤0.05 at days 50 and 60) there was already a significant decrease in PE, AUC and A (p≤0.05 at days 40–60) in treated animals compared to controls. However, for kep and ADC there were no significant differences between the groups at any time point (p>0.05 at days 40–60). In conclusion, anti-angiogenic treatment response in osteolytic breast cancer bone metastases can be assessed early with surrogate markers of vascularization, while DWI appears to be insensitive.

Contrast-enhanced ultrasound is helpful in the differentiation of malignant and benign breast lesions

Hongjia Zhao, Rong Xu, Qiufang Ouyang, Lidian Chen, Baowei Dong, Ye Huihua — 2010-02-01

Abstract: Objective: To evaluate the significance of contrast-enhanced ultrasound (CEUS) examination in differential diagnosis of malignant and benign breast lesions.Methods: Seventy-one patients with seventy-six breast tumors are selected randomly. CEUS examinations were performed before and after bolus injection of the contrast agent SonoVue (Bracco, Milan, Italy). Specific sonographic quantification software, Qontrast, was adopted to determine the morphology of vessels. Wash-in and wash-out parameters of each lesion were assessed for both procedures.Results: The final histopathological findings distinguished 45 malignant and 31 benign from all of the lesions. Following SonoVue administration different perfusion phases could be identified: early (0–1min), mid (1–4min) and late (4–6min) phases. In the early phase, CEUS identified 91.1% of malignant tumors characterized by a claw-shaped enhancement, while 83.9% of benign tumors had a homogeneous enhancement, with a statistically significant difference between the two enhancement patterns (χ2=43.16, P<0.01). Moreover, contrast medium persistence in the late phase was helpful in the identification of benign and malignant tumors (χ2=46.88, P<0.01): contrast medium was present in 88.9% of malignant tumors, while in only 9.7% of the benign tumors. The study showed that various parametric imaging color maps for peak intensity and time to peak were mostly suggestive of malignancy, while quite uniform peak intensity and time to peak of color maps were the characteristic of benign tumors. The study also found that malignant lesions presented with a higher maximum intensity signal than benign ones (P<0.05) on the time–intensity curves.Conclusions: CEUS cooperating with conventional US shows improved accuracy in differentiating between malignant and benign breast tumors. It could be a reliable diagnostic method of breast lesions.

Integrated contrast-enhanced diagnostic whole-body PET/CT as a first-line restaging modality in patients with suspected metastatic recurrence of breast cancer

2010-02-01

Abstract: Objective(s): Only few information exist about the diagnostic accuracy of PET/CT for restaging patients with metastatic recurrence of breast carcinoma. Therefore, our study hypothesis was to perform diagnostic contrast enhanced CT (ce-CT) and FDG-PET in a one-step investigation, to prove sensitivity of each modality and to determine whether diagnostic PET/CT adds information over PET or contrast enhanced CT alone for restaging of patients with suspected recurrence of breast cancer.Methods: Fifty-two patients with suspected recurrence of breast cancer were included in our study. All of them were free of metastasis after the first line therapy. Indications for restaging were: Elevated tumor markers n=32, clinical deterioration n=16 and/or suspicious findings on other imaging studies n=48. Integrated PET/CT was performed using contrast-enhanced diagnostic CT for attenuation correction.Results: PET was correct in 44/52 patients (85%), ce-CT in 38/52 patients (73%) and PET/CT in 50/52 patients (96%). Sensitivity and specificity of lesion detection of PET, CT and PET/CT were 84%, 66% and 93%, and 100%, 92%, and 100%, respectively.Discussion: PET/CT can improve staging and alter therapeutic options in patients suspected to have breast cancer recurrence and distant metastatic disease, primarily by demonstrating local or distant nodal involvement occult at other imaging studies. The added value of FDG-PET/CT over other diagnostic modalities is mainly expressed by the fact that a noninvasive whole-body evaluation is possible in a single examination.

Monitoring of liver glycogen synthesis in diabetic patients using carbon-13 MR spectroscopy

2010-02-01

Abstract: To investigate the relationship between liver glucose, glycogen, and plasma glucose in diabetic patients, in vivo liver carbon-13 magnetic resonance spectroscopy (13C MRS) with a clinical 3.0T MR system was performed. Subjects were healthy male volunteers (n=5) and male type-2 diabetic patients (n=5). Pre- and during oral glucose tolerance tests (OGTT), 13C MR spectra without proton decoupling were acquired in a monitoring period of over 6h, and in total seven spectra were obtained from each subject. For OGTT, 75g of glucose, including 5g of [1-13C]glucose, was administered. The MR signals of liver [1-13C]glucose and glycogen were detected and their time-course changes were assessed in comparison with the plasma data obtained at screening. The correlations between the fasting plasma glucose level and liver glycogen/glucose rate (Spearman: ρ=−0.68, p<0.05, n=10) and the fasting plasma glucose level and liver glycogen peak/fasting rate (Spearman: ρ=−0.67, p<0.05, n=10) indicated that 13C MRS can perform noninvasive measurement of glycogen storage/degradation ability in the liver individually and can assist in tailor-made therapy for diabetes. In conclusion, 13C MRS has a potential to become a powerful tool in diagnosing diabetes multilaterally.

Comparison between two-point and four-point methods for quantification of apparent diffusion coefficient of normal liver parenchyma and focal lesions. Value of normalization with spleen

2010-02-01

Abstract: Purpose: To compare two quantification techniques of apparent diffusion coefficient (ADC), both in normal liver parenchyma and focal lesions, and to investigate any potential value of normalization.Materials and methods: Fifty-six consecutive patients underwent MRI examination of the liver, including a single shot spin-echo echo planar imaging diffusion sequence with four b-values (0, 50, 500 and 1000s/mm2). ADC maps were reconstructed based on a two-point method (b-values: 500 and 1000s/mm2) and a four-point method (b-values: 0, 50, 500 and 1000s/mm2). Comparison of absolute ADC measurements of the liver, benign and malignant focal lesions was performed between the two- and four-point techniques. The same analysis was done on normalized ADC values (absolute ADC values divided by spleen ADC values).Results: The difference between mean two-point and four-point ADC values of normal liver (absolute: 1.237×10−3, 1.615×10−3mm2/s, normalized: 1.40, 1.52, respectively) was statistically significant (p<0.0001 and p=0.0061). Significantly higher absolute ADC values of benign and malignant lesions were recorded with the four-point method (2.860×10−3 and 1.307×10−3mm2/s) over the two-point method (2.243×10−3, and 1.011×10−3mm2/s) (p<0.0001 in both) while the same differences in normalized values were proven statistically non-significant for benign lesions (p=0.788) and statistically significant for malignant lesions (p=0.015). Both differences in absolute and normalized ADC values of benign versus malignant lesions based on two- and four-point methods were found to be significant (p<0.0001).Conclusion: ADC quantification of the liver may be performed with a two-point method (b-values of 500 and 1000s/mm2), while normalization of ADC measurements with the spleen is not further improving lesion characterization.

Prediction of vascular involvement and resectability by multidetector-row CT versus MR imaging with MR angiography in patients who underwent surgery for resection of pancreatic ductal adenocarcinoma

Jeong Kyong Lee, Ah Young Kim, Pyo Nyun Kim, Moon-Gyu Lee, Hyun Kwon Ha — 2010-02-01

Abstract: Purpose: To compare the diagnostic value of dual-phase multidetector-row CT (MDCT) and MR imaging with dual-phase three-dimensional MR angiography (MRA) in the prediction of vascular involvement and resectability of pancreatic ductal adenocarcinoma.Methods and materials: 116 patients with proven pancreatic adenocarcinoma underwent both MDCT and combined MR imaging prior to surgery. Of 116 patients, 56 who underwent surgery were included. Two radiologists independently attempt to assess detectability, vascular involvement and resectability of pancreatic adenocarcinoma on both images. Results were compared with surgical findings and statistical analysis was performed.Results: MDCT detected pancreatic mass in 45 of 56 patients (80.3%) and MR imaging in 44 patients (78.6%). In assessment of vascular involvement, sensitivities and specificities of MDCT were 61% and 96% on a vessel-by-vessel basis, respectively. Those of MR imaging were 57% and 98%, respectively. In determining resectability, sensitivities and specificities of MDCT were 90% and 65%, respectively. Those of MR imaging were 90% and 41%, respectively. There was no statistical difference in detecting tumor, assessing vascular involvement and determining resectability between MDCT and MR imaging (p=0.5).Conclusion: MDCT and MR imaging with MRA demonstrated an equal ability in detection, predicting vascular involvement, and determining resectability for a pancreatic ductal adenocarcinoma.

Diagnostic imaging in Merkel cell carcinoma: Lessons to learn from 16 cases with correlation of sonography, CT, MRI and PET

2010-02-01

Abstract: Objective: The authors report imaging findings in a series of 16 patients with MCC, a rare tumour which is often managed primarily by a dermatologist. To our knowledge, no equivalent series of MCC has been described in the nuclear medicine literature.Material and Methods: In this IRB-approved retrospective noncomparative case series 16 patients with biopsy-proven Merkel cell carcinoma were included between January 1999 and October 2007. Twenty-nine whole body PET scans (18F-FDG n=24, 18F-FDOPA n=5) in 16 patients were retrospectively reviewed with regard to tracer uptake in six anatomical sites per patient. For 127/144 of FDG-PET evaluated regions and 68/144 of regions depicted by conventional imaging methods, a valid standard of reference could be obtained. A combined standard of reference was applied, which consisted of histopathology (lymphadenectomy or biopsy) or clinical or radiological follow-up for at least 12 months. Results: the mean FDG uptake over the clinicopatholigical verified FDG avid areas was 4.7 SUV (1.5–9.9 SUV). The region based assessment of diagnostic value, in consideration of the standard of reference, resulted in a sensitivity of 85.7% and a specificity of 96.2% of FDG-PET (n=127) and in a combined sensitivity of 95.5% and a specificity of 89.1% for morphological imaging methods (n=68). Differences between methods did not reach statistical significance (p=1.00, p=0.18).Conclusions: FDG-PET is a highly useful whole body staging method of comparable value compared to conventional imaging methods with restricted field of view. The lessons learned from case series are discussed.

Performance of integrated FDG-PET/contrast-enhanced CT in the staging and restaging of colorectal cancer: Comparison with PET and enhanced CT

2010-02-01

Abstract: Objective: The purpose of this study was to assess the diagnostic value of PET/CT as a one step examination in patients with colorectal cancer. Therefore we proved whether diagnostic PET/CT adds information over PET or contrast-enhanced CT alone for staging or restaging of patients with colorectal cancer.Methods: Seventy-three patients (46 males and 27 females; age range: 50–81 years; mean age: 67 years) with known colorectal cancer underwent 18F-FDG-PET/CT for staging or restaging.Results: Of the 73 patients 26 patients underwent PET/CT for staging and 47 for restaging. 266 metastases could be detected in 60 patients. Contrast-enhanced PET/CT had a lesion-based sensitivity of 100%, contrast-enhanced CT of 91% and PET of 85%. PET/CT identified 2 lesions as false positive. PET/CT could also reach a patient-based sensitivity of 100%, which was superior to contrast-enhanced CT and PET.Conclusion: Our study clearly demonstrated the added value of contrast-enhanced PET/CT in staging and restaging patients with colorectal cancer over CT and PET alone.

Rectal villous tumours: MR features and correlation with TRUS in the preoperative evaluation

2010-02-01

Abstract: Aim: The aim of this study was to assess the clinical relevance of MR and transrectal ultrasonography (TRUS) imaging of rectal villous tumours to elucidate the correlation between imaging results and specific histopathological tumour features, such as tumour size (T) and lymph node involvement (N), in order to establish the better technique for the pre-surgical patient evaluation.Patients and methods: 23 cases of villous tumours of the rectum were studied with phased-array MR and TRUS. All patients underwent either surgical or endoscopic treatment. Final diagnosis was based on histopathological results. In particular, the following features were characterized by the imaging techniques mentioned above: lesion site, distance between lesion and ano-rectal junction, size, morphology and contrast enhancement of lesions, fluid layer around the lesion, alterations of the deep layers of the rectal wall, sphincter infiltration, presence or absence of mesorectal, iliac and obturatory lymphnode involvement.Results: Histology established muscular involvement in 7 cases (T2), perirectal fat infiltration in 1 case (T3); in the remaining 15 cases, staging was Tis-T1. In 17/23 cases (73.9%) the lesions were correctly staged with both imaging techniques, whereas in 5/23 cases (21.7%) the lesions were overstaged. No cases were understaged. TRUS concorded with histological exams in 17/23 cases (73.9%). 5/23 cases (21.7%) were overstaged and 1/23 (4%) was understaged. MR and TRUS were in accordance in 20/23 cases (86.9%).Discussion: Considering the frequent degeneration of villous tumours, correct preoperative identification and precise evaluation of these lesions, such as the detection of rectal wall invasion, is essential in deciding optimal treatment strategy. MRI and TRUS allow the identification of specific features of villous tumours and of malignant degeneration, allowing for a correct local disease staging.

Performance of computed tomographic urography in diagnosis of upper urinary tract urothelial carcinoma, in patients presenting with hematuria: Systematic review and meta-analysis

2010-02-01

Abstract: Computed tomographic urography (CTU) is a relatively new diagnostic imaging technique, which combines the diagnostic advantages introduced by helical tomographic imaging, with the established technique of imaging during the renal excretory phase, into one single examination. Increasing availability of multidetector computed tomography (MDCT) units, further promotes the technique as the “one-stop-shop” for the imaging investigation of patients with haematuria. We reviewed and meta-analyzed published literature, in order to evaluate the performance of CTU for the detection of upper urinary tract urothelial tumors. CTU proved to be a very sensitive and specific method for the detection of urothelial malignancy, with sensitivity ranging between 88% and 100%, and specificity between 93% and 100%. Pooled sensitivity was 96% (95% CI: 88–100%) and pooled specificity was 99% (95% CI: 98–100%). Direct comparison of the method with intravenous urography (IVU), confirmed the superiority of CTU over IVU in terms of sensitivity and specificity. Major drawbacks of CTU are increased radiation risk, injection of iodinated contrast media which may potentially be accompanied by serious side effects and increased cost, estimated as roughly three times that of IVU. According to our study, CTU is the method of choice for the detection of pathology in “high risk” haematuria patients, i.e. patients older than 40 years of age presenting with gross haematuria.

Long-term results of symptomatic fibroids treated with uterine artery embolization: In conjunction with MR evaluation

Man Deuk Kim, Hyun Seok Lee, Mee Hwa Lee, Hee Jin Kim, Jin Ho Cho, Sun Hee Cha — 2010-02-01

Abstract: Objective: The aim of the present study is to determine long-term clinical efficacy of uterine fibroid embolization (UFE) for symptomatic fibroids in conjunction with MR evaluation.Materials and methods: Sixteen patients with a follow-up period of 4 years or longer were analyzed retrospectively. Ages ranged from 27 to 45 (mean 39.5) years. Mean follow-up periods were 5.8 years (range: 4.1–6.9 years). The symptom changes, in terms of menorrhagia and dysmenorrhea and bulk-related symptoms, were assessed. The primary embolic agent was polyvinyl alcohol particle (250–710μm). All patients underwent preprocedural and long-term follow up MR imaging. Uterine volumes were calculated using MRI.Results: Symptom improvements were reported for menorrhagia (8/9, 88.9%), dysmenorrhea (5/5, 100%), and bulk-related symptoms (7/9, 77.8%) at long-term follow up. Two patients (12.5%) had symptom recurrences at long-term follow-up. Tumor regrowth from incomplete infarction was a cause of recurrence in one patient and newly developed leiomyomas in the other one.One patient underwent hysterectomy because endometriosis developed 4 years after UFE.Of the 14 necrotic myomas on short-term follow up MR after UFE, eight (57.1%) demonstrated maintaining necrosis with further shrinkage and six (42.9%) were no longer visualized on long-term follow up MR images. Overall, the mean volume reduction rates of the predominant fibroid and uterus were 80.5%, 36.7% at long-term follow up, respectively.Conclusion: UFE is an effective treatment for symptomatic fibroids with an acceptable long-term success rate. Long-term MR imaging after UFE revealed persistent necrotic fibroid, non-visualization of fibroids and tumor regrowth when incompletely infarcted.

1H-MRSI of prostate cancer: The relationship between metabolite ratio and tumor proliferation

2010-02-01

Abstract: Purpose: To investigate whether 1H-MRSI can be used to predict the proliferative activity of prostate cancer.Materials and methods: Thirty-eight patients with prostate cancer (PCa) and thirty-three patients with benign prostate hyperplasia (BPH) were included in this study. Patients were examined in supine position using a 1.5T superconducting magnetic scanner equipped with a pelvic phased-array multi-coil and CSI-3D-PROSTATE sequence. Commercial software was used to acquire and process MR spectroscopic imaging data. Mean (Cho+Cr)/Cit ratios of PCa, BPH, and peripheral zone (PZ) were calculated. Cellularity of PCa was recorded based on hematoxylin and eosin staining. PCNA was detected using immunohistochemical techniques.Results: The mean (Cho+Cr)/Cit ratio of the peripheral zone (0.38±0.09) was lower than that of BPH (0.51±0.19) (P<0.05). The average value of (Cho+Cr)/Cit ratio of prostate cancer was 3.98±0.12. The (Cho+Cr)/Cit ratio of prostate cancer was higher than that of the peripheral zone and BPH (P<0.05). The cellularity and PCNA LI of prostate cancer were 12.90±4.07% and 72.1±19.01%, respectively. The (Cho+Cr)/Cit ratio of prostate cancer positively correlated with tumor cellularity (r=0.582, P=0.027) and PCNA LI (r=0.495, P=0.022).Conclusion: The (Cho+Cr)/Cit ratio of PCa can reveal the differences in proliferative activity between PCa and BPH. MRSIs are therefore able to predict the proliferative rate of variously differentiated prostate cancers.

A qualitative approach to combined magnetic resonance imaging and spectroscopy in the diagnosis of prostate cancer

Geert M. Villeirs, Willem Oosterlinck, Els Vanherreweghe, Gert O. De Meerleer — 2010-02-01

Abstract: Purpose: To investigate the feasibility and diagnostic value of a whole prostate qualitative approach to combined magnetic resonance imaging and spectroscopy (MRI+MRS) in the detection of prostate cancer in patients with elevated PSA.Materials and methods: Three hundred and fifty six subjects (mean serum PSA 11.47ng/ml, range 0.40–133ng/ml) were examined with fast-T2-weighted images (MRI) and 3D-magnetic resonance spectroscopy (MRS). Both modalities were qualitatively analyzed on a whole prostate basis by a single radiologist using a 4-point diagnostic scale. Prostate cancer was histopathologically proven in 220 patients and non-evidence of cancer was determined after at least 12 months clinical follow-up in 136 subjects.Results: Receiver operating curve analysis revealed a significantly better diagnostic performance of MRI+MRS (Az=0.857) than MRI alone (Az=0.801) and MRS alone (Az=0.810). The sensitivity, specificity and accuracy of MRI+MRS for detection of prostate cancer were 72.3%, 92.6%, and 80.1%, respectively.Conclusions: Spectral evaluation with a whole prostate qualitative approach is feasible in routine clinical practice. The combination of MRI and MRS yields superior diagnostic results than either modality alone.

Prevalence of nephrogenic systemic fibrosis in renal insufficiency patients: Results of the FINEST study

2010-02-01

Abstract: Purpose: Nephrogenic systemic fibrosis (NSF) is characterized by widespread tissue fibrosis, mainly affecting the skin. Gadolinium chelates have been implicated in the onset of NSF in patients with renal impairment (RI). The FINEST study (FIbrose Néphrogénique SysTémique) was designed to determine the prevalence of NSF after magnetic resonance imaging (MRI) in French RI patients.Materials and methods: We studied all patients with RI who had at least one MRI examination during a one-year period, with or without gadolinium chelate administration. Data were collected retrospectively from 9 Nephrology Departments in France, and included sex, age, renal function, type of gadolinium administered, and subsequent cutaneous disorders. If a patient presented a cutaneous disorder, a skin biopsy was performed to confirm the diagnostic.Results: The 308 eligible patients had a mean age of 59.9 years, 59% were men, and 54% had stage 5 RI. 75% of those 308 patients received a Gadolinium chelate. Among those patients who received a gadolinium chelate, 76% received gadoterate, 20% gadopentetate, 3% gadodiamide and 1% gadobenate. No cutaneous disorders were recorded after MRI.Conclusion: These results confirm that NSF is a rare disease. Based on a reported frequency, ∼3.5% in patients with glomerular filtration rate <30ml/min/1.73m2), some cases should have been observed in our study which included 308 patients. Most patients received gadoterate, a macrocyclic gadolinium chelate for which no case of NSF has been observed worldwide. This suggests that more stable macrocyclic agents may be less likely to induce NSF.

High correlation between quantitative ultrasound and DXA during 7 years of follow-up

Penelope Trimpou, Ingvar Bosaeus, Bengt-Åke Bengtsson, Kerstin Landin-Wilhelmsen — 2010-02-01

Abstract: Ultrasound is a quick, cheap and non-radiating device for assessing bone quality. We wanted to validate the method for clinical and epidemiological use.Eighty women, aged 53–73 years, with osteoporosis and/or fractures were followed repeatedly during 7 years. Quantitative ultrasound (QUS) measurements (LUNAR Achilles) were compared with bone mineral density (BMD) and bone mineral content (BMC) estimated by DXA (LUNAR) in regions of interest.Changes in the speed of sound, broadband ultrasound attenuation and stiffness were positively correlated with changes in BMD and BMC in all regions measured with DXA (r=0.20–0.53; p=0.09 to <0.0001). The QUS t-score at the left heel was positively correlated with the t-score at the right heel (r=0.90, p<0.0001). The DXA t-score of the left vs. the right femur was also positively correlated (r=0.72–0.86; p<0.0001).A t-score<−2.5 S.D. was found in 70% and 56% at baseline, and 74% and 65% at follow-up measured with QUS and DXA, respectively. The mean sensitivity of QUS vs. DXA was 79% and the mean specificity 45% over a 7-year period. A QUS t-score of <−3.65 S.D. was consistent with a DXA t-score of <−2.5 S.D.In conclusion, QUS was well correlated with DXA in all regions over the 7-year period. QUS can be used in settings without access to DXA and in epidemiological studies. The sensitivity was high but the specificity was low, implicating that DXA, if available, is recommended before treatment for osteoporosis. However, treatment can be started without DXA at a QUS t-score<−3.65 S.D., and especially in the presence of fractures.

Chronic lower extremity lymphedema: A comparative study of high-resolution interstitial MR lymphangiography and heavily T2-weighted MRI

Qing Lu, Jianrong Xu, Ningfei Liu — 2010-02-01

Abstract: Purpose: To assess the role of heavily T2-weighted image and interstitial MR lymphangiography (MRL) for the visualization of lymphatic vessels in patients with disorders of the lymphatic circulation.Methods: Forty lower extremities in 31 patients (9 bilateral and 22 unilateral) with primary lymphedema were examined by heavily T2-weighted image and indirect MRL. Maximum-intensity projection (MIP) was used to reconstruct the images of the lymphatic system. Two experienced radiologists analyzed the images with regard to the differences in image quality, number of lymphatic vessels, its maximum diameter and two other findings: accumulated lymph fluid in the tissue and honeycombing pattern.Results: The beaded appearance of the affected vessels in 73 leg segments of 40 lower extremities were present on both modalities 3D MIP. Larger amount of the dilated lymphatic vessels were visualized on heavily T2-weighted image than that on MRL (p=0.003) and the maximum diameter of it was 4.28±1.53mm on heavily T2-weighted image, whereas 3.41±1.05mm on MRL (p<0.01). The dilated lymphatic vessels on MRL showed better image quality and greater SNR and CNR than that on heavily T2-weighted image (p<0.01). The regions of accumulated lymph fluid and the honeycombing pattern extent were identified on heavily T2-weighted image scored statistically higher than that on MRL (p<0.01).Conclusion: The heavily T2-weighted imaging has greater sensitivity and the MRL image has higher legibility for detecting the pathologically modified lymphatic vessels and accompanying complications non-invasively. Combining these two MR techniques can accurately access the pathological changes in the lower extremity with lymphedema.

Radiofrequency ablation in the treatment of osteoid osteoma—5-year experience

2010-02-01

Abstract: Purpose: This study aimed to determine the success and complication rates of radiofrequency ablation (RFA) in treatment of osteoid osteoma (OO) and duration of pain relief. Furthermore value of bone biopsy prior to the RFA was evaluated.Materials and methods: Within 61 months 39 patients (23 male, 16 female, 7–53 years, mean 18.7 years, median 17 years) suffering from osteoid osteoma were treated. Lesions were located in femur (n=20), tibia (n=10), spine (n=5), humerus (n=1), radius (n=1), talus (n=1) and pelvis (n=1). In children, RFA was performed under general anaesthesia, in adults conscious sedation was preferred. In 29 of 39 (74%) lesion biopsies were obtained. Cooling of skin was performed in OOs located in bones with minor soft tissue covering (tibia, radius) and saline flushing via an additional needle was performed if the OO was adjacent to nerval structures. Primary success rate, complications, symptom-free interval, follow-up and biopsy results were evaluated.Results: Within observation period (1–61 months; median: 32 months) 38 of 39 patients were successfully treated and had no more complaints. In 3 of 38 patients relapse occurred after 1, 14 and 32 months and RFA was repeated. Two major complications (broken drill, infection) and 2 minor complications (hematoma, prolonged pain) were observed. Biopsy was able to prove diagnosis in 14 of 29 (48%) cases.Conclusions: Biopsy prior to treatment is not mandatory due to a remarkable amount of false negative findings in clinically and morphologically unambiguous cases of OO. RFA is a highly effective, efficient, minimally invasive and safe method for the treatment of OO.

Transarterial microcatheter glue embolization of the bronchial artery for life-threatening hemoptysis: Technical and clinical results

2010-02-01

Abstract: Objectives: To report our experience with transarterial glue embolization of the bronchial artery for life-threatening hemoptysis.Materials and methods: Twenty-five patients underwent bronchial artery embolization, using coaxial microcatheter technique, with a liquid agent, n-butyl-2-cyanoacrylate (NBCA), named glue, for life-threatening hemoptysis. The technical and clinical outcomes were followed in terms of immediate control of bleeding, recurrence of hemoptysis and complications of the procedure.Results: Four patients had acute hemoptysis when they were evaluated. The average number of arteries embolized per patient was 2.9. BAEs were successful in controlling hemoptysis immediately in all 25 patients (100%) and in 24 patients (96%) at 1 month follow-ups. One patient had recurrent hemoptysis on the tenth day after embolization. The follow-up time ranged from 2 to 63 months (mean 14 months). Six patients (25%) died all as a result of their disease process. Bleeding recurred in 3 patients after 30 days (7th, 11th, 12th months). One patient had vomitting attacks with dysphagia after the procedure that lasted 24h. Three patients had transient thoracic pain lasting 3–5 days. There were no procedure related spinal or vascular complications.Conclusions: Glue embolization with microcatheter technique is a safe and effective treatment in cases of life-threatening hemoptysis with a very high rate of success and low rate of complications.

Prevention of biliary complication in radiofrequency ablation for hepatocellular carcinoma—Cooling effect by endoscopic nasobiliary drainage tube

2010-02-01

Abstract: Background and study aims: Biliary stricture after radiofrequency ablation (RFA) for nodules of hepatocellular carcinoma (HCC) close to major bile ducts sometimes causes septic complications and liver failure. Therefore, it may require interventional drainage for decompression during the follow-up period. The purpose of this study is to clarify the feasibility and safety of bile duct cooling using an endoscopic nasobiliary drainage (ENBD) tube in RFA for HCC close to major bile ducts.Patients and methods: Between August 2003 and July 2007, 14 consecutive patients (14 nodules) undergoing RFA with cooling by an ENBD tube for HCCs close to major bile ducts were enrolled in this study. We infused chilled saline solution via the ENBD tube at 1ml/s to prevent heat damage during RFA. As controls, 11 patients (13 nodules) undergoing RFA without cooling close to major bile ducts between April 2001 and August 2003 were reviewed. The major outcomes for evaluation were biliary complications and the secondary outcome was local tumor recurrence.Results: There were no significant differences in tumor recurrence between the two groups. However, the rate of biliary complications was significantly lower in the cooling group than in the non-cooling group (0% vs. 39%, P=0.02).Conclusions: Cooling of bile ducts via an ENBD tube can prevent biliary complications induced by RFA of HCC close to major bile ducts without increasing local recurrence. This technique increases indication of RFA in difficult cases.

Pushable springcoil embolization of pseudoaneurysms caused by gluteal stab injuries

Koray Guven, Izzet Rozanes, Adem Ucar, Arzu Poyanli, Hakan Yanar, Bulent Acunas — 2010-02-01

Abstract: Purpose: To retrospectively review the outcomes of 21 patients with stab wounds to the gluteal region who underwent embolization for pseudoaneurysms causing active bleeding.Materials and methods: Between 1997 and 2007, 3 superior gluteal artery, 2 inferior gluteal artery and 16 deep femoral artery muscular branch pseudoaneurysms detected by digital subtraction angiography were selectively catheterized with diagnostic catheters with hydrophilic coating and embolized with pushable springcoils. 17 of the 21 pseudoaneurysms were located in a distal end of an artery where outflow vessels could not be depicted. The other 4 lesions were side wall injuries which required the placement of coils distal and proximal to the injury site.Results: Embolization was successful in controlling the bleeding in all of the patients. 16 patients required 1 or 2 coils, 4 patients required 3 coils and 1 patient required 5 coils. 2 patients had femoral puncture site hematomas which resolved spontaneously. 2 patients required surgical evacuation of large gluteal hematomas following the embolization because of symptoms second to mass effect. There were no procedure related major complications or mortality.Conclusions: Our experience demonstrates that pushable coil embolization is a relatively simple, effective and economic method for the embolization of pseudoaneurysms caused by penetrating gluteal injuries. Experimenting with other embolization materials does not seem to be justified.

Feasibility of magnetic resonance imaging-guided high intensity focused ultrasound therapy for ablating uterine fibroids in patients with bowel lies anterior to uterus

2010-02-01

Abstract: Purpose: To prospectively evaluate the feasibility of magnetic resonance (MR) imaging-guided high intensity focused ultrasound (HIFU) therapeutic ablation of uterine fibroids in patients with bowel lies anterior to uterus.Materials and methods: Twenty-one patients with 23 uterine fibroids underwent MR imaging-guided high intensity focused ultrasound treatment, with a mean age of 39.4±6.9 (20–49) years, with fibroids average measuring 6.0±1.6 (range, 2.9–9.5)cm in diameter. After being compressed with a degassed water balloon on abdominal wall, MR imaging-guided high intensity focused ultrasound treatment was performed under conscious sedation by using fentanyl and midazolam. This procedure was performed by a Haifu® JM focused ultrasound tumour therapeutic system (JM2.5C, Chongqing Haifu Technology Co., Ltd., China), in combination with a 1.5-Tesla MRI system (Symphony, Siemens, Germany), which provides real-time guidance and control. Contrast-enhanced MR imaging was performed to evaluate the efficacy of thermal ablation immediately and 3 months after HIFU treatment. The treatment time and adverse events were recorded.Results: The mean fibroid volume was 97.0±78.3 (range, 12.7–318.3)cm3. According to the treatment plan, an average 75.0±11.4% (range, 37.8–92.4%) of the fibroid volume was treated. The mean fibroid volume immediately after HIFU was 109.7±93.1 (range, 11.9–389.6)cm3, slightly enlarged because of edema. The average non-perfused volume was 83.3±71.7 (range, 7.7–282.9)cm3, the average fractional ablation, which was defined as non-perfused volume divided by the fibroid volume immediately after HIFU treatment, was 76.9±18.7% (range, 21.0–97.0%). There were no statistically significant differences between the treatment volume and the non-perfused volume. Follow-up magnetic resonance imaging (MRI) at 3 months obtained in 12 patients, the fibroid volume decreased by 31.4±29.3% (range, −1.9 to 60.0%) in average, with paired t-test showing a statistically significant reduction (P=0.002). The mean treatment time for ablating the average 83.3±71.7 (range, 7.7–282.9)cm3 of fibroid volume was 2.5±1.4h (range, 27–390min) in this study, which was relatively short and acceptable to patient and therapist. Four patients experienced mild skin burn (two with skin redness, two with blisters), the skin burn subsided within ∼2 days. No other adverse events were observed.Conclusions: After the bowel was compressed with a degassed water balloon, MR imaging-guided high intensity focused ultrasound treatment is safe and feasible in ablating uterine fibroids in patients with bowel lies anterior to uterus.

The role of interventional radiology in obstetric and gynaecology practice

2010-02-01

Abstract: Interventional radiology is continuing to reshape current practice in many specialties of clinical care. It is a relatively new and innovative branch of medicine in which physicians treat diseases non-operatively through small catheters guided to the target by fluoroscopic and other imaging modalities. The aim is to provide image-guided, minimally invasive alternatives to traditional surgical and medical procedures in suitable cohorts of patients. Procedures which previously required major surgery can now be performed by interventional radiologists, sometimes on an outpatient basis, with little patient discomfort. In this review, we highlight the importance of interventional radiology in treating a comprehensive range of obstetric and gynaecological pathologies.

Heated lipiodol as an embolization agent for transhepatic arterial embolization in VX2 rabbit liver cancer model

2010-02-01

Abstract: Purpose: To evaluate the therapeutic effect of heated (60°C) lipiodol via hepatic artery administration in a rabbit model of VX2 liver cancer.Materials and methods: Thirty male New Zealand white rabbits were randomly divided into three groups with 10 rabbits assigned to each group. VX2 carcinoma cells were surgically implanted into the left hepatic lobe. The tumors were allowed to grow for 2 weeks, and studies were performed until the diameter of the tumors detected by ultrasonograph reached 2–3cm. Under anesthesia, trans-catheter hepatic arterial embolization was performed and doxorubicin-lipiodol (37°C) (1mL), lipiodol (60°C) (1mL) or control (physiological saline (37°C) (1mL)) solution was injected into the hepatic arteries of animals in the three groups. One week later, the volume of the tumor was measured by ultrasonograph again. The serum of all rabbits was collected before injection and at 4 and 7 days after injection, and the level of aspartate aminotransferase (AST) was checked. The survival period of the three groups of rabbits after treatment was also recorded. During the last course of their disease, the rabbits were given analgesics to relieve suffering.Results: The tumor growth rate in the lipiodol (60°C) group (0.92±0.21, tumor volume from 1811±435 to 1670±564mm3) was significantly lower than that in the control group (3.48±1.17, tumor volume from 1808±756 to 5747±1341mm3) (P<0.05) and in the doxorubicin-lipiodol (37°C) group (1.69±0.26, tumor volume from 1881±641 to 2428±752mm3) (P<0.05). Consequently, the survival period of the animals in the lipiodol (60°C) group (41.0±3.0 days) was significantly greater than that in the doxorubicin-lipiodol (37°C) group (38.0±2.5 days) (P<0.05). On the other hand, there was no statistically significant difference in serum AST levels between the lipiodol (60°C) group (148.2±11.3UL−1) and the doxorubicin-lipiodol (37°C) group (139.7±12.3UL−1) (P>0.05). However, the serum AST level in the lipiodol (60°C) group was significantly higher at 4 days after injection (P<0.05) than in the control group (68.6±6.6UL−1).Conclusions: Treatment with lipiodol (60°C) resulted in an effect on serum AST levels similar to that caused by treatment with doxorubicin-lipiodol (37°C). Thus, lipiodol (60°C) treatment could greatly prolong the survival period of rabbits with VX2 cancer by inhibiting tumor growth.

Gd-EDDA/HYNIC-RGD as an MR molecular probe imaging integrin ανβ3 receptor-expressed tumor—MR molecular imaging of angiogenesis

Tianlong Huo, Xiangke Du, Sen Zhang, Xia Liu, Xubing Li — 2010-02-01

Abstract: Rationale and objective: The aim of this study is to develop a novel MR probe containing arginine–glycine–aspartic acid (RGD) motif for imaging integrin ανβ3 receptor-expressed tumor.Materials and methods: Commercially available HYNIC-RGD conjugated with co-ligand EDDA was labeled with Gd3+, and the mixture was isolated and purified by solid phase extract (SPE) to get the entire probe Gd-EDDA/HYNIC-RGD. Human hepatocellular carcinoma (HHCC) cell line BEL-7402 was cultured and the cells harvested and suspended in serum-free Dulbecco's modified Eagle medium (DMEM) were subcutaneously inoculated into athymic nude mice for tumor growth. In vitro cell binding assay to integrin ανβ3 receptor and cell viability experiments were conducted. The in vivo imaging of the three arms of xenografts were performed by MR scan with a dedicated animal coil at time points of 0, 30, 60, 90min and 24-h post-intravenous injection (p.i.). Three arms of nude mice then were sacrificed for histological examination to confirm the imaging results.Results: Gd-EDDA/HYNIC-RGD was successfully isolated by SPE and validity was verified on signal enhancement through in vitro and in vivo experiments. The nude mice model bearing HHCC was well established. There was approx. 30% signal enhancement on T1WI FSE images at 90min post-intravenous injection of the Gd-EDDA/HYNIC-RGD compared with baseline, and the signal to time curve is straightforward over time in the span of 0–90min p.i., while the control arms do not show this tendency.Conclusion: Gd-EDDA/HYNIC-RGD has the potential to serve as an MR probe detecting integrin ανβ3 receptor-expressed tumor.

Low dose multi-detector CT of the chest (iLEAD Study): Visual ranking of different simulated mAs levels

2010-02-01

Abstract: Purpose: Detailed evaluation of the lung parenchyma might be impaired by use of low dose CT as image noise increases and subsequently image quality decreases. The aim of our study was to determine the accuracy of visual perception of differences in image quality and noise at low dose chest CT.Materials and methods: Forty-four patients suffering from emphysema underwent CT (Aquilion-16, 120kV, 150mAs, 1mm-collimation). Original raw data were used for simulation of 10 different mAs settings from 10mAs to 100mAs in 10mAs increments. Three representative hard copy images (carina, 4cm above, 5cm below) were printed for evaluation of lung parenchyma (high-resolution kernel, lung window) and mediastinum (soft-kernel, soft tissue window). Ranking of expected low mAs level was performed for lung and soft tissue separately based on visual perception by three-blinded chest radiologist independently. Results were compared to the real simulated mAs.Results: The accuracy for correct ranking of the original 150mAs scan was 89% for lung and 86% for soft tissue while it was 99% for the simulated 10mAs for both windows. In comparison to the lowest mAs a significant error increase was found for the lung at 60–100mAs (with error increase of 30–47%) for reader-I; 60–100mAs for (33–64%) for reader-II and 70–100mAs (38–57%) for reader-III. For the soft tissue: 60–150mAs (with error increase of 28–63%) for reader-I; 50–100mAs (35–56%) for reader-II and 50–90mAs (35–40%) for reader-III.Conclusion: Simulated dose levels below 60mAs (=42mAseff) were clearly differentiated from higher dose levels by all readers. Therefore, imaging doses could be lowered down to 60mAs without a diagnostically relevant increase in noise impairing image quality.

Respiratory gated multidetector computed tomography: Applicable for diagnostic abdominal imaging?

2010-02-01

Abstract: Purpose: To evaluate the ability and accuracy of a respiratory gated technique used with contrast enhanced MDCT of the upper abdomen with focus on diagnostic image quality and depiction of organs and major vessels.Materials and methods: Forty-five adult patients who were referred to our institution for follow-up dynamic contrast enhanced abdominal CT imaging were included in this study. Respiratory gated CT scans were performed with the use of a dedicated hardware. A multiphasic CT scan was performed for each patient. Respiratory gated images were obtained between early arterial and portal venous phases during free breathing. Images of respiratory gated (RG) and breathhold (BH) phases were compared qualitatively and quantitatively by two radiologists. Definitive statistical methods were used for evaluating the scoring data, while Mann Whitney U test was used for comparison. Statistical significance was accepted for p values <0.05.Results: Statistical significant difference was found for comparison of scores regarding luminal opacification and contoural integrity of intrahepatic vascular structures with scores of RG scans rated poor to moderate (e.g. 2.86±1.07 for luminal opacification of intrahepatic portal veins as well as border detectability) in comparison to scores of BH scans rated good to excellent (e.g. 1.37±1.31 for luminal opacification, 1.35±1.28 for border detectability of intrahepatic portal veins, p<0.001). Furthermore, statistical significant differences were found for general image noise levels (p<0.001).Conclusions: Further technical advances of RG technique could enable routine use of this technique for selected patient groups.

Impact of image noise levels, scout scan dose and lens shield on image quality and radiation exposure in z-axis dose-modulated neck MSCT on 16- and 64-slice Toshiba Aquilion scanners

2010-02-01

Abstract: Objective: Assessing the impact of image noise (IN) levels, scout scan dose and lens shield use on image quality and radiation exposure in neck multislice CT (MSCT) when using z-axis dose modulation (DM).Methods: Neck MSCT phantom studies with/without z-axis DM were performed by using different IN levels (S.D. 7.5–30HU) and scout scan tube currents (7.5–50mA) on Toshiba Aquilion scanners (16-/64-slice). Image quality indices were evaluated by two radiologists and radiation exposure parameters calculated. Cadaveric phantom measurements elucidated lens shield interactions with DM efficacy. The lowest dose scan protocol with diagnostic image quality was introduced into the clinical imaging routine and retrospectively evaluated in 20 age-matched patients undergoing neck MSCT with/without DM.Results: The highest image noise level in DM neck studies with comparable image quality to standard neck CT amounted to 20HU, resulting in a mean tube current of 50mAs (CTDIw 6.3mGy). DM reduced effective dose by 35% and organ dose figures (lens, thyroid) by 33%. Scout scan dose lowering to 20mA resulted in an effective dose (ED) decrease of 0.06mSv (5%). Avoiding lens shield placement during scout scan effected an organ dose decrease of 20%. Overall contour sharpness and image contrast did not differ significantly (DM/without DM) whereas image noise was rated higher in DM neck CT studies (p<0.05).Conclusions: z-Axis dose modulation, as assessed on 16- and 64-slice Toshiba Aquilion scanners, is effective and mandatory in neck MSCT. DM efficacy can be enhanced by optimising scout scan doses and lens shield use.

Stephan Gentzsch — 2010-02-01

This new edition thoroughly reviews all aspects of the effects of ionizing radiation on humans, incorporating important developments occurring in the past nine years. Up-to-date information, compiled from studies on radiation therapy, accidental or occupational exposures, and atomic bomb survivors, includes: assessment and comparison of various radiation sources, assessment of radiation-induced genetic effects, a discussion of radiation induced cancer effects and an evaluation of the literature: the organs, late effects of radiation, radiation and pregnancy, and determining whether specific effects are caused by radiation.

Stephan Gentzsch — 2010-02-01

Covering all on breast cancer, containing 4GB of data, 3000 electronic pages and more than 60 original charts this unique DVD is a must-have for radiologists but is relevant to gynaecologists, oncologists, surgeons and general practitioners specialized in women's health care.

Vanessa Kulemann — 2010-02-01

This reference textbook and atlas provides a good overview about cardiac CT of the adult heart comprising normal anatomy and pathology. The initial chapters review the basics of performing cardiac CT, including indications, technical features, and protocols. The subsequent chapters explain the role of calcium scoring as a predictive factor for cardiovascular disease and the CT scoring technique. Coronary artery disease and post-interventional evaluation of stents and grafts are well discussed, with numerous representative images. Cardiac morphology and function, as well as valve assessment and interventional procedures with complex cardiac investigations, are covered in the final chapters. The included DVD contains more than one hundred informative clips about cardiac function.

Christian Loewe — 2010-02-01

Interventional techniques have gained increasing importance in the treatment of malignoma and associated conditions. Due to the improvement of such techniques and the integration of these interventional techniques in oncological treatment during the last years, image-guided or “interventional” techniques play now an important role not only in tumor palliation, but even in curative cancers. Reflecting this evolution Interventional Radiologists worldwide are now important partners and contributors to institutional tumor boards. The number of “interventional” techniques is exciting, and it seems sometimes, that more or less everything might be possible for Interventional Radiologists. This enormous selection of different techniques leads to establishment of further sub-sub-specialties, of the non-vascular or oncological Interventional Radiologist.

Calendar of Events

2010-02-01

Short Instructions to Authors

2010-02-01